Antirust agent



Patented Feb. 6, 1951 UNITED STATES PATENT OFFICE ANTIRUST scam HastingsS. Trigg, Henry D. No

White, Pitman,

West mama, N. Y., and N Vgoodbury, and Ralph V.

assignors to Socony- Vacuum Oil Company, Incorporated, a corporation ofNew York No Drawing. Original application February 8, 1947, Serial No.727,304. Divided and this application November 24, 1948, Serial No.61,916 12 Claims. 260-313) This inventionrelates to certain newcompolecular weight of the primary amine. Products sitions of matterformed by the interaction of having as little as 1.25 molecularproportions of alkenyl succinic acid anhydrides and primary alkenylsuccinic acid anhydride to 1 molecular amines.

Various alkenyl succinic acids and their anhydrides, and many primaryamines are known, and some of these have been added to lubricating oilsfor various purposes. Insofar as is known, however, no reaction productsof alkenyl succinic acid anhydrides with primary amines have beenprepared.

According to the present invention, it has been discovered that alkenylsuccinic acid anhydrides may be reacted with primary amines to producereaction products 01' an entirely new type. Certain of these reactionproducts when added to lubricating oil, effectively inhibit theformation of rust, even in the presence of sea water. The effectivenessof these new reaction products in inhibiting rust formation is indistinct contrast to the properties of the reactants from which theproducts are made, which exhibit little or no tendency to inhibit rustformation under the same conditions.

The new reaction products, when added in minor amounts to lubricatingoil, not only inhibit rust formation on metals immersed therein orcoated thereby, but have no deleterious eifect on the lubricating oil inother respects, and probably improve the lubricating oil in othercharacteristics as well as in its rust inhibiting characteristics. V

REAC'IANTS The new reaction products may be prepared from any alkenylsuccinic acid anhydride, or any mixture thereof, and with any primaryamine or mixture of primary amines. Either the anhydride or the aminemay be used in a chemically pure or commercial state, and either may bea single compound or a mixture of a number of compounds. The amine maybe an alkyl, aryl, cycloalkyl or heterocyclic amine, or may c0ntain anycombination of organic radicals. Normal primary alkyl amines arepreferred.

Alkenyl succinic acids may, less desirably, be used in place of theiranhydrides, although this necessitates much more careful removal ofwater and often produces considerable amounts of undesirableby-products.

The preferred proportions in which the reactants are reacted is twomolecular weights of the alkenyl succinic acid anhydride to onemoproportion of primary amine have been found effective in inihibitingrust when incorporated in lubricating oil, and products having more than2 molecular proportions of alkenyl succinic acid anhydride to 1molecular proportion of primary amine are also effective for thispurpose, although it does not appear that 1 molecule of primary aminecan react with more than 2 molecules of alkenyl succinic acid anhydrideandthe eifect of using more than 2 molecular proportions of alkenylsuccinic acid anhydride is, therefore, apparently merely to dilute thefinal product with the excess of alkenyl succinic acid anhydride.

Products efiective as rust inhibitors in lubricating oil can be preparedfrom primary amines having as few as 4 carbon atoms in the alkyl chain,provided the alkenyyl succinic acid anhydride contains about 10 to 12carbon atoms or more in the alkenyl radical. On the other hand, reactionproducts efiective as rust inhibitors in lubricating oil can be preparedfrom alkenyl succinic acid anhydrides containing as few as 6 to 8 carbonatoms in the alkenyl radical if the primary amine contains around 12carbon atoms in the alkyl chain. From this it appears that the totalnumber of carbon atoms contained in the reactants is a critical factorwhen the reaction product is to be used as a rust inhibitor inlubricating oil; The indications are that the total number of carbonatoms in 2 mols of the anhydride and 1 mol of the amine should be noless than about 28 and preferably no less than 32 to give a product thatwill substantially inhibit rust when incorporated in lubricating oil innormal concentrations. A smaller total number of carbon atoms will giveproducts which have some anti-rust activity, if the products are used inhigher concentrations. The preferred reactants for producing rustinihibiting agents for use in oil are alkenyl succinic acid anhydridescontaining about 10 to 12 carbon atoms in each alkenyl chain and primaryamines containing about 10 to 14 carbon atoms per molecule.

REACTION CONDITIONS The reaction of the anhydride with the primary amineis quite easy of accomplishment and may be carried out in any number orways, either actions or deterioration of the reactants or the It isdefinitely preferable to reaction product.

between about 105 C. and

use a temperature of about 115 C.

The time of reaction does not appear to be especially critical, theneutralization number of the flnal product indicating that the reactionis substantially complete in around 3 /2 hours at the preferredtemperature. Time and temperature are, however, interdependent, and alonger period of time is required at lower temperatures.

Further details of this invention and further advantages may beunderstood from the following detailed examples and results of tests.

In the examples, commercial alkenyl succinic acid anhydrides have beenused. Instead of being a single, pure, chemical compound, thesecommercial anhydrides are mixtures of alkenyl succinic acid anhydridesin which the alkenyl side chains range generally between certain limits.Thre different products were used in the following examples, one ofwhich was a mixture of alkenyl succinic acid anhydrides in which thealkenyl radicals averaged 6 to 8 carbon atoms in length, a second was asimilar mixture of anhydrides in which the alkenyl radicals averaged 8to 10 carbon atoms in length, and the third, a similar mixture ofanhydrides in which the alkenyl radicals ranged from 10 to 12 carbonatoms in length. The general structure for these compounds may beconsidered to be:

ail-0 where R is a mixture of alkenyl groups having an average of from 6to 8, 8 to 10, or to 12 carbon atoms. The mixtures used in the followingexamples were those manufactured and sold by the Solvay Process Companyof New York, New York.

The primary amines used in the following examples were likewise of acommercial quality, rather than chemically pure, except whereotherwiseenoted. These commercial-quality primary amines are 97% pureand contain predominantly the number of carbon atoms indicated. Thecommercial amines used in the following examples are manufactured andsold by Armour 8: Company of Chicago, Illinois under the tradenamesArmeen CD, Armeen SD, Armeen 8D, "Armeeni 10D,f Armeen 12D, Armeen 14D,Armeen 16D,[ and Armeen 18D. Armeen CD is a mixtureof primary aminesprepared from coconut oil, Armeen SD is a mixture of primary aminesprepared from soybean oil, and the other "Armeens are mixtures ofprimary amines containing predominantly the number of carbon atomsspecified in the code number. Theoretical neutralization numbers arebased on the assumption that the amine can neutralize half of theavailable acidity in the anhydride.

EXAMPLE I A commercial Clo-l2 alkenyl succinic acid an-' in a beaker14.5 g. of the anbydride and 5.0 g. of the amine. The reactants werestirred together, the heat of reaction raising the temperature to about80 C. The mixture was then placed in an oven at 105-1l0 C. for about 1hour. The reaction product was a fairly viscous, amber coiored liquidwith a neutralization number (milligrams of KOH equivalent to l g. ofproducts) of 191. The theoretical neutralization number of this productwas calculated to be 140.

EXAMPLEII A commercial Clo-ll alkenyl succinic acid anhydride wasreacted with "Armeen 101)" in a closed flask in the absence of air byplacing 80 g. of the anhydride in a a-necked, 200 cc. flask flushed withnitrogen gas, and heating the anhydride to 109 0., still in anatmosphere of nitrogen. 15.9 g. (0.1 g. excess for drainage) of Armeen10 was then placed in a dropping funnel in which an atmosphere ofnitrogen gas was maintained during the subsequent operation, and thisamine was added dropwise to the anhydride at a rate sufilcient to raisethe temperature in the flask to 113 C. and to maintain it at thattemperature without the application of external heat. After the additionof the amine was completed, the flask was heated and stirred at 115 C. v

for 3 hours. The product was a dark, amber colored viscous liquid andthere was no deposit on the walls of the flask. The neutralizationnumber of the product was 161.9, whereas theoretically it should havebeen 152.9.

A number of other products were prepared by the above methods by usingdifferent amines and different anhydrides. In the tables which follow,

' the manner of preparation will be designated by a numeral I or II,these numerals serving to designate that the product was prepared inaccordance with Example I or in accordance with Example II,respectively. In general, the procedure of Example 11 has been foundpreferable. As an indication of the length of time necessary toaccomplish the desired reaction two mols of a Ca-io commercial alkenylsuccinic acid anhydride and one mol of Armeen CD were heated at C. in aflask and portions removed from time to time and tested forneutralization number to determine the progress of the reaction. Thechange in neutralization number is shown in the The theoreticalneutralization number for this product is 158. The indication thereforeis that the reaction was substantially complete in a period of about 3hours. The eflectiveness of the various products prepared in accordancewith this invention, as rust inhibitors, was determined in accordancewith ASTM Test D665-44T for determining Rust Preventing Characteristicsof Steam Turbine Oils in Presence of Water. In accordance with thistest, both synthetic sea water and distilled water are used. Thesynthetic sea water contained 25 g. of sodium chloride, 11 g. ofmagnesium chloride (MgC1:.6H:O), 4 g. of sodium sulphate and 1.2 g. ofcalcium chloride per liter. In the test a cylindrical, polished steelspecimen is suspended and soaked in 300 cc. of the oil under test at 140F. for 30 minutes. 30 cc. of synthetic sea water (or 30 cc. of distilledwater) are added and the mixture is stirred at 1000 R. P. M. After 48hours the steel specimen is removed and examined for evidence sion layerafter 30 minutes. See Tables II, III and IV, pages 11, 12 and 13.

Similar tests were conducted on the alkenyl succinic acid anhydridesused in preparing the reaction products and hydrolyzed aikenyl succinicacid anhydrides. These tests indicated that they are not satisfactoryrust inhibitors in themselves. Results of these tests are shown in TableV, page 14.

of rust. The oil passes the test when there is no Further tests weremade of the reaction prodevidence of rust on that part of the specimenucts of Own: alkenyl succinic acid anhydrides which hangs below the oillevel. and Armeen 10D,-reacted in various molar pro- In the followingtests, various of the reaction portions and reacted at varioustemperatures to products of this invention were blended with a indicatethe effect of proportions and tempera.- base oil commonly used for rustinhibiting tests. ture on the effectiveness of the products as rust Thisoil was a blend of a solvent refined Midinhibitors. The results of thesetests are shown Continent residual stock with a, solvent refined inTable VI, page 16. Mid-Continent (Rodessa) distillate stock which Theresults of the test on page 16 indicate that gives an oil having aspecific gravity of 0.872, a it is necessary to use temperatures inexcess of fiashpoint of 445 F. and a Saybolt Universal vistO P u the p er d ype of p o u ts cosity of 407.7 seconds at 100 F. Such an oil is andthat it is desirable to use a molar ratio 0t suitable for use in steamturbines. at least 1.25 to l of anhydride to. amine in order Todetermine whether or not the addition of to produce the preferred typeof products. The the reaction products of this invention to oilsproducts prepared at 75 C. and the products cause the formation ofundesirable emulsions, P p d using a 1 t0 1 molar ratio d d S ow semulsion tests were also conducted on the oilrust inhibitingcharacteristics. However, the reaction product mixtures in accordancewith the data obtained indicate that it is distinctly preferemulsiontest for lubricating oils described in able to use a molar ratio of atleast 1.25 to 1 and the Federal Stock Catalog, Sec. IV, Part 5, Federala temperature in excess of 75 C. In order to Specifications VV-L-79lb,February 19, 1942. In 0 obtain the most satisfactory type of product, itaccordance with the'test method 320.13, 40 cc. of is far preferable touse a temperature of 105 C. oil and 40 cc. of a standard emulsant areplaced above in e p p o o t e reaction in a 100 cc. cylinder and stirredwith a paddle at products. 1500 R. P. M. for 5 minutes at the prescribedtem- Tests of oils containing other additives in addiperature.Separation of the emulsion is observed t n t t reaction u ts f thisinvention while the cylinder is kept at the prescribed temperature forthe specified time. The figures in the tables show the number of minutesduring which an emulsion layer persists between the oil and theemulsion. An oil is usually considered not to be emulsive if there is nocontinuous emulhave indicated that no incompatibility exists and thatpractically any other additive which it is desired to add may be addedwithout affecting the beneficial results obtained by the addition of thereaction products of this invention and without impairing theeffectiveness of the other additives.

TABLE II Products of 2 moles (ho-12 anhydride and 1 mole primary amineA. S. T. M. Rust Test Govt. Emulsion Method N eutralizagfi'l Break, Min.Amine Used of Prepon Na B1 en d5, Synthetic Seawater Distilled Waterration Per Cent Result Remarks Result Remarks H20 1% NaCl Armeen on I191.6 0.10 Pass Gray coat 0.05 do do 0.02 do Light gray coat" 0.01Fall... 10-15 spots 0. 005 Don I 191. 4 0.05 Pass Gray coat 0. 003 Do I168.0 0.05 Pass Gray coat n-Butylamine I 167. 4 1). 8g ..-do Heagy graycoat.

. o n-Octylamine I 183. 3 0. 05 d Armeen 8D I 188.2 0.05 d

' 0.02 0.01 Armeen 10D I 188. 8 0. 05 Do II 161. 9 0. 05 0.02 0.01 0.003 Perfect; 0. 001 Severe rust.. Armeen 12D I 176. l 0.05 Armeen 14D-.I 1Y6. 3 0. 05 Armeen 1611. I 169.9 0.05 Armeen l8D I 157. l 0I05 0. 02Armeen SD I 175. 1 0. 05 14 15 Cyclonexylamine I 191.3 0.05 12 12Benzylamina. I 175. 5 0. 05 l7 l4 Aniline I 180. 8 0. 05 16 14 TABLI VIReaction products 0] C104: anhydrides and Armeen MD in various molarproportions-tested by A.

S. T. M. rust test in synthetic seawater Products Prepared at 115 0.Products Prepared at 75 C. Concen- MOIBS 0f M0105 t ti A s T R of Q 13Neumb A. s. T. M. Rust Test N eutral- Test mine Percent imtion imtionNo. No.

Result Remarks Result Remarks 2 1 0.05 161.9 Pass Heavy coat 212.4Fail-.. 50s ts.

0.03 d0 Light ooat 0.02 d ..---d0 0.01 1.75 1 0.05 0.04 0.03 0.02 1.5 10.05 0.04 0.03 0.02

Tests conducted by a modification of the proposed A. S. T. M. method oftesting the oxidation characteristics of steam turbine oils (whichmethod is now designated as D943-47T) according to which modificationthe oxidation-inhibited oil is subjected to a temperature of 203 F. (95C.) in the presence of water, oxygen (3 liters per hour), and aniron-copper coil suspended in the oil above the water layer, for aperiod of 1000 hours, also indicated that the of this invention arehighly effective as rust preventatives;

The results of Brown-Boveri turbine oil tests have also been verysatisfactory and show that the reaction products of this inventionimpart no sludging properties or other undesirable characteristics tothe oxidation-inhibited oil blends in which they are incorporated.

Atmospheric corrosion tests further indicate that oil compositionscentage of the reaction products of this invention are highly effectivein preventing atmospheric corrosion.

This application is a division of application Serial No. 727,304 filedFebruary 8, 1947, now D. Patent 2,490,744.

What is claimed is:

1. As a new composition of matter, the reaction product obtained byreacting an acidic reactant selected from the group consisting of analkenyl succinic acid anhydride, an alkenyl succinic acid, and mixturesof alkenyl succinic acid anhydrides and of alkenyl succinic acids with aprimary amine reactant selected from the group consisting of a primaryamine and a mixture-oi prim ry amines, in a molar proportion of at least1.25:1, respectively, and at a temperature varyinc between about 75 C.and about 140 C.

2. As a new composition of mat er. t e rcaction product obtained byreacting an alkenyl succinic acid anhydride with a primary amine, in amolar proportion of at least 1.25:1, respectively, and at a temperaturevarying between about 75 C. and about 140 C.; the sum of twice thenumber of carbon atoms per molecule of said alkenyl succinic acidanhydride and of the number of carbon atoms per molecule of said primaryamine being at least 28.

3. As a new composition of matter, the reaction product obtained byreacting an alkenyl sucreaction products 3.

including a minor peri.-

cinic acid anhydride with a primary, aliphatic amine, in a molarproportion of at least 1.25:1, respectively, and at a temperaturevarying between about C. and about 140 C.; the sum of twice the numberof carbon atoms per molecule of said alkenyl succinic acid anhydride andof the number of carbon atoms per molecule of said primary amine beingat least 28.

4. As a new compositon of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride, having between about sixand about eight carbon atoms per alkenyl radical, with a primary amine,having at least about eight carbon atoms per molecule, in a molarproportion of at least 1.25:1, respectively, and at a temperaturevarying between about 75 C. and about 140 C.

5. As a new composition of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride, having between about eightand about ten carbon atoms per alkenyl radical, with a primary amine,having at least about four carbon atoms per molecule, in a molarproportion of at least 1.25:1, respectively, and at a temperatugevarying between about 75 C. and about 14 C.

6. As a new composition of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride, having between about tenand about twelve carbon atoms per alkenyl radical, with a primary amine,having at least about four carbon atoms per molecule, in a molarproportion of at least 1.25:1, and at a temperature varying betweenabout 75 C. and about 140 C.

7. As a new composition of matter, the reaction product obtained byreacting an alke'nyl succinic acid anhydride, having between about sixand about eight carbon atoms per alkenyl radical, with dodecylamine, ina molar proportion of about 2:1, respectively, and at a temperaturevarying between about C. and about C.

8. As a new composition of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride, having between about eightand about ten carbon atoms per alkenyl radical, with aniline, in a molarproportion of about 2:1, respectively, and at a temperature varyingbetween about 105 C. and about 115 C.

9. As a new composition of matter, the reaction product obtained byreacting an alkenyl succal, with a primary,

tween about 105 C. and about 115 cinic acid anhydride, having betweenabout ten and about twelve carbon atoms per alkenyl radialphatic amine,having between about ten and about fourteen carbon atoms per molecule,in a molar proportion of about 2:1, respectively. and at a temperaturevarying be- 10. As a new composition of matter, the reaction productobtained by reacting an aikenyl succinic acid anhydride, having betweenabout ten and about twelve carbon atoms per alkenyl radical, with aprimary, aliphatic amine prepared from coconut oil, in a molarproportion of about 2:1, respectively. and at a temperature varyingbetween about 105 C. and about 115 C.

11. As a new composition of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride having between about ten andabout twelve carbon atoms per alkenyl radical, with cyciohexylamine, ina molar proportion 2,182,178

or about 2:1, respectively, and at a temperature varying between aboutC. and about C.

12. As a new composition of matter, the reaction product obtained byreacting an alkenyl succinic acid anhydride, having between about tenand about twelve carbon atoms per alkenyi radical, with butylamine, in amolar proportion of about 2:1, respectively. and at a temperaturevarying between about 105 C. and about C.

HASTINGS S. TRIGG. HENRY D. NORRIS. RALPH V. WHITE.

' nan-mamas 0mm The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date Pinkernelle Dec. 5. 1939 Number

1. AS A NEW COMPOSITION OF MATTER, THE REACTION PRODUCT OBTAINED BYREACTING AN ACIDIC REACTANT SELECTED FROM THE GROUP CONSISTING OF ANALKENYL SUCCINIC ACID ANHYDRIDE, AN ALKENYL SUCCINIC ACID, AND MIXTURESOF ALKENYL SUCCINIC ACID ANHYDRIDES AND OF ALKENYL SUCCINIC ACIDS WITH APRIMARY AMINE REACTANT SELECTED FROM THE GROUP CONSISTING OF A PRIMARYAMINE AND A MIXTURE OF PRIMARY AMINES, IN A MOLAR PROPORTION OF AT LEAST1.25:1, RESPECTIVELY, AND AT A TEMPERATURE VARYING BETWEEN ABOUT 75* C.AND ABOUT 140* C.